Pump



1964 P. s. GIOVAGNOLI 3,156,139

PUMP

Filed July 23, 1962 2 Sheets-Sheet l INVENTOR. Paul S. iovagflo/i UnitedStates Patent 3,156,189 PUMP Paul S. Giovagnoii, 4200 Birmingham Road,Kansas City 17, M0. Filed July 23, 1962, Ser. No. 211,544 1 (Ilairn.(Cl. 103-47) The invention relates to pumping apparatus, and moreparticularly, to a piston pump for pressurizing liquids.

It is the most important object of this invention to provide pumpingapparatus capable of effective operation against a high head of liquidpressure so that the apparatus may be utilized to impart relatively highpressure to liquids.

Another important object of the invention and in the accomplishment ofthe foregoing object, is the provision of pumping apparatus driventhrough an eccentric for imparting a very short stroke to the pumppiston so that extremely high pressure may be imparted to the liquid bya single pumping operation.

Still a further object of the instant invention is the provision ofpumping apparatus having a minimum of moving parts and constructed ofdurable materials so that effective operation for long periods ispossible with maintenance and repair kept to a minimum.

Another highly important object of this invention is the provision ofsuch apparatus constructed of readily and commercially available partsso that the apparatus may be quickly and easily fabricated with a bareminimum of costly machining operations.

In the drawings:

FIGURE 1 is a side elevational view of pumping apparatus embodying theprinciples of the instant invention, the cylinder inlet filter havingbeen removed to reveal details of construction and parts broken away forclearness;

FIG. 2 is a fragmentary, front elevational view of the apparatus of FIG.1;

FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 1;

FIG. 4 is an enlarged, fragmentary, vertical, cross-sectional view ofthe pumping apparatus showing the cylinder, piston means and base block;

FIG. 5 is a fragmentary, plan view of the base block of FIG. 4 with thecylinder and base plate removed to reveal the exhaust valve and spring;

HG. 6 is a cross-sectional view taken along line 66 of FIG. 4; and

FIG. 7 is a front elevational View of the pressure control switchutilized with the apparatus of this invention, a portion of the housingthereof being broken away to reveal details of construction.

Briefly, this invention relates to a pump comprising a pistonreciprocated through short stroke at relatively high speed in a cylinderby a prime mover operably coupled to the piston through an eccentric.The cylinder is provided with a fluid inlet and an outlet whichcommunicates into the chamber of a thick walled base block opening intoa pressure tank. Suitable check valves are provided in the piston andacross the outlet to cause a fluid flow through the chamber and into thetank, A compressible bladder in the tank serves as a buffer to absorbthe impact and pulsations of the fluid as it enters the tank.

Manually controlled fluid discharge means permits the removal ofpressurized fluid from the tank. A pressure relief switch operates whenthe pressure in the tank reaches a predetermined value to discontinueoperation of the pump until the pressure drops a predetermined amount,at which time it operates to resume the pumping operation. The switch isadjustaole to permit operation at selected pressures to maintain asubstantially uniform pressure in the tank. 1

, 3,156,189 Patented Nov. 10, 1964:

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The pumping apparatus designated 10 in FIG. 1, includes a tubular,upright pressure tank 12; which may be constructed from a section ofpipe or the like closed at its upper end by a cap 14, and having a primemover such as an electric motor 16 bolted thereto through a bracket 18secured to motor 16 and attached to a mounting plate 2%) which may berigidly secured to the outer wall of upright tank 12 by welding or thelike. A tubular housing 22 containing bearings (not shown) journalingshaft 24, is secured to tank 12 by means of a brace member 26 extendingbetween plate 249 and housing 22 and also by means of a metallic strap28 passing around housing 22 and having the ends thereof secured to theouter wall of tank 12 as by welding.

A pulley wheel 39 is rigidly secured to one end of shaft 24 whichprojects outwardly from housing 22, and a pulley wheel 32 on the shaftof motor lti is alignable with wheel 39 with a V-belt 34 providingdriving connection between motor 16 and shaft 24. An eccentric, broadlydes ignated 36, is secured to the opposite end of shaft 24 and comprisesa driving member 38 having an offset boss ill operably coupled with adriven member 42 so that rotation of shaft 24 provides a verticalcomponent of motion to driven member 42. It will be noted that boss 4t)is spaced radially from the axis of rotation of shaft 24, but suchspacing is a relatively short distance so that the vertical component ofmotion of driven member 42 is relatively short.

An elongated drive shaft 44 has the upper end thereof secured to drivenmember 42 and is bifurcated at its lower end to present a pair ofspaced, parallel legs 46 receiving therebetween the upper end of apiston 48 best shown in FIG. 6.

Piston 43 includes an elongated bar of durable material such as asynthetic resin which may be nylon, and has an aperture 59 passingthrough the upper end thereof to receive a pin 52 which has its endssecured in legs 46 for pivotally coupling piston 48 to shaft 44. Aportion of piston 43 is of reduced diameter and is slidably receivedwithin a cylinder 54 having its lower end closed by a base plate 56. Twopairs of aligned openings 58 in the outer wall of cylinder 54 provideinlet means for permitting fluid to flow into cylinder 54, and tofacilitate such flow the piston 48 is provided with fourcircumferentially spaced grooves 60 having generally arcuate bottomsurfaces 62.

The lower end of piston 48 is provided with a bore '64 whichaccommodates a check valve broadly designated 66, and comprising atubular, flanged mounting element 68 externally threaded for threadedengagement in the outer portion of bore 64. Element 68 has an annularrim 7t) on the outer face thereof which provides a seat for a flat,disc-like member 74 which is normally secured in its seated position bya helical spring 74 engaging the inner end of element 68 and a nut 76threadably engaged on a bolt 78 passing through member 72 and spring 74.A second nut 8h may be provided to lock nut 76 in place and permit theinadvertent disengagement thereof from bolt 78.. A guide broadlydesignated 82, comprising a plurality of upwardly extending legs 84disposed to engage the inner and annular surface of element 68, is

secured to member 72 to insure that the latter shifts into and out ofits position on seat 70. An aperture 36 is provided through the surfaced2 of each groove 60 in piston 48 and communicates with bore 64 topermit fluid to flow therethrough.

It should be noted that the outer surface of piston 48 is spacedslightly inwardly from the inner surface of cylinder 54 and a cup $8 ofrelatively flexible material is secured to the bottom end of piston 48by a Washer 9% held in placeby the outwardly extending flange of element63 and spans the distance across cylinder 54- in sliding fluid sealingrelationship with the latter. A hole 92 passes through base plate asbeneatn check valve 66 and communicates the inner cavity of cylinder 54with a chamber 94- formed in a relatively large block 96 of materialsuch as steel or the like.

It Will be noted that chamber 94 is spaced inwardly from the outersurfaces of block 96 to provide Walls of relatively great thickness forchamber 94. A bore 98 extending downwardly from the upper surface ofblock 96 beneath hole 92, receives a generally flat, disc-like exhaustvalve member tilt) therein and the latter is provided with outwardlyextending ears 102 projecting from the outer peripheral edge of member1% to relatively close proximity to the iner surface of bore 98. It willbe noted that the inner, generally circular portion of member 1% is ofsubstantially lesser diameter than bore 93 to provide means forpermitting the flow of fluid past memher 160. A downwardly projectingrim 104 on the under surface of base plate 56 provides a seat for membertilt? which is held in its normally seated position on rim 1% by ahelical spring 1% engaging the lower surface of chamber 94. One end ofchamber 94 is closed by a plug 168 threadahly engaged in block 96, andthe other end of chamber 94- turns upwardly and opens into tank 12 whichis secured to the upper surface of block 96 as by Welding. It should benoted that base plate 56 is secured to block 96 by means of bolts 110extending through holes 112 in block 96 and threadably engaged insuitable openings therefor in plate 56.

A tubular neck 114 extends outwardly from tank 12 around an aperture(not shown) in the outer wall of tank 12 and receives a nipple 116 whichis threadably engaged in a T fitting 125 to which is coupled a flexiblehose 12 3 having a manual valve broadly designated 122 operably coupledwith nozzle means broadly designated 124, which provides means fordischarging fluid from within tank 12 through nozzle means 124.

Pressure control means broadly designated 126, is operably coupled tothe other opening of T 118 and comprises an electrical switchingstructure 128 operably coupled with a flexible diaphragm 139 foroperation of electrical contacts (not shown) upon the condition ofdeformation of the diaphragm under the influence of the fluid pressurewithin tank 12. To this end, the fluid inlet 132 of pressure controlmeans 126 is placed in fluid communication with T 118 by pipe 134.

Pressure control means 126 comprises any of a number of commerciallyavailable, adjustable electrical switching devices, forms no part of theinstant invention per se, and will not be described in detail. Itsuflices to say that control means 126 may be adjusted to operate toopen the electrical contacts thereof upon the attainment of apredetermined amount of fluid pressure within tank 12 and to operate toclose the contacts when the fluid pressure in tank 12 has dropped toanother predetermined pressure value. The electrical power lines (notshown), supplying motor 16 with electrical energy are connected throughswitch 128 by terminals 136, 138, 140 and 142. Thus, when the fluidpressure within tank 12 reaches the predetermined value which causesswitch 128 to open its contacts, motor 16 is de-energized to halt thepumping operation. As soon as the fluid pressure within tank 12 drops tothe predetermined pressure permitting switch 128 to close its contacts,the motor is again energized to resume the pumping operation to maintainthe fluid pressure within tank 12 at the desired value. Dcsirably,pressure control means 126 is adjusted to provide a differential betweenthe pressure values at which switch 128 is operated to open and closeits contacts respectively. It has been found that 625 psi. is a suitablepressure for de-energizing motor 16, and 400 psi. is a suitable pressurevalue to resume the pumping operation to maintain an efflcicnt sprayingpressure value within tank 12.

In FIG. 2, cylinder 54 is shown with a filter screen 192 disposed insurrounding relationship thereto to per- 4t mit the flow of fluid intocylinder 54, through openings 58, but to prevent the ingress of foreignmaterial.

A bracket 1% is rigidly secured to tank 12 and anchors one end of a pairof springs 198, while the other end thereof is anchored to a bracket 200rigidly secured to shaft 44. Springs 193 exert a force on shaft 44,tending to bias the latter toward the position thereof shown in FIG. 1,with piston 48 at the bottom of its stroke in cylinder 54.

Preferably, a pressure gauge 202 is mounted On cap I and communicateswith tank 12 through a nipple 204 to permit ready reading of thepressure within tank 12. Bracket means broadly designated 2% andincluding a generally flat plate 208 secured to tank 12 by any suitablemeans such as U-bolt 216, and a pair of integral, generally outwardlyflared extensions 212 having generally U-shaped notches 214- opening inthe bottom edges thereof, provide means for mounting tank 12 in anupright position in a gallon drum or the like with the rim of the drumdisposed in notches 214-. If desired, auxiliary clamping apparatus (notshown) may be provided to releasably secure apparatus it} in the drum.It will be readily understood that apparatus 10 may similarly bedisposed in any vessel containing fluid.

An elongated, tubular bladder 216 of flexible material such as a rubberhose or the like, is disposed within tank 12. Bladder 216 is closed atone end and the other end communicates with a valve stem 218 throughnipple 2M and a T 2&5 to permit bladder 2E6 to be filled with air for apurpose to be made clear hereinafter.

In operation, apparatus 10 is disposed in a source of liquid withopenings 53 immersed in the liquid and motor 16 is operably coupled witha source of electrical energy (not shown) for operating the motor anddriving shaft 24 through V-belt 34. The rotation of shaft 24 operateseccentric 36 to impart a relatively short, vertical stroke to shaft 44-and thus to piston 4-8 in cylinder 54. Preferably, motor 16 operates ata speed to provide a relatively high speed to the stroke of piston 48.

On the up-stroke of piston 4-8, the fluid which has entered throughopenings 58 into grooves and thence into bore 64 through apertures 86,is permitted to flow past check valve 66 inasmuch as helical spring 74permits valve member '72 to shift from its normally seated position onthis stroke. It should be noted that valve member 1% is seated insealing relationship on rim 104 to prevent the flow of fluid from withinchamber 94 and into cylinder 54. After piston 48 reaches its uppermostposition, its direction is reversed and valve member 72 returns to itsnormally seated position with cup 88 sealing against flow of the liquidbetween the cylinder 54 and piston 48. Thus, as the piston 48 proceedsdownwardly, the fluid is forced through hole 92 to unseat valve member1%. The fluid then flows into chamber 94. As the pumping operationcontinues, the fluid in chamber 94 is in turn forced upwardly into tank12 Where it is pressurized by the continued operation of the pumpingapparatus.

As the fluid from each stroke of piston 43 is forced into tank 12, theimpact of such fluid entering the tank is absorbed by bladder 216 toprevent damage to the tank and to prevent pulsations of the fluid. Therapid, elatively short strokes of piston 48 permit the operation of thepiston against an extremely high head of pressure and it is possible toelevate the pressure of the liquid within tank 12 to relatively highvalues through one pumping operation. As piston 48 continues to operateto elevate the pressure Within tank 12 to a value approaching thepredetermined shut-ofl pressure, diaphragm 132 is shifted under theinfluence of the pressur in tank 12 to operate switch 128 andtie-energize motor 16.

If valve means 122 is opened to permit fluid to spray through nozzle12%, the pressure in tank 12 may drop to a value that is below thepressure at which switch 128 operates to close its contacts andre-energize motor 16 to resume the pumping operation.

The thick walled construction of block 96 prevents damage to apparatusimmediately below piston 48 Where the impact of the compression impartedby the piston is the most severe. The high speed, relatively shortstroke of piston 48 permits the achievement of extremely high pressurevalues with apparatus 10, and the construction of piston 48 from durablethermoplastic synthetic resin material permits reciprocation of thepiston at high speed without damage thereto caused by the highpressures. The water acts as a lubricant and coolant medium so that thepiston may move at a very high velocity without being darn-aged. Pistonsconstructed of nylon or Delrin have been found to give the best results.

It should be noted that the construction of apparatus 10 is largely fromrelatively inexpensive materials which are readily commerciallyavailable, and the necessity for costly machine operations has been keptto a minimum. This permits the provision of pumping apparatus forproviding high pressure liquid for uses such as spraying operations inestablishments Where cost of the apparatus must be kept to a minimum.Specifically, the apparatus is ideally suited for utilization forspraying operations in filling stations where high pressure is requiredfor the cleaning of motors by liquid containing detergents. Also, otherWashing operations at filling stations may be advantageously performedwith apparatus constructed according to the principles of thisinvention.

It Will be readily understood that the utility of apparatus 10 is by nomeans limited to use with filling stations and that the apparatus willhave a wide range of applicability.

Having thus described the invention, what is claimed as new and desiredto be secured by Letters Patent is:

Pumping apparatus for pressurizing liquid comprising:

a cylinder provided with a liquid inlet and a liquid outlet, said inletcomprising a series of openings communicating with the interior of thecylinder and spaced circumferentially therearound;

piston means reciprocable in the cylinder for forcing liquid from thecylinder through the outlet, said piston means including an elongatedbody of synthetic resin rna-teral having a plurality ofcircumferen-tially spaced, longitudinally arcuate grooves adjacent theopenings of said cylinder, there being a groove for each openingrespectively, there being a longitudinaly extending bore in the bodycommunicating with one end of the latter, said body having an aperturefor each groove communicating the respective grooves with said bore, anda valve carried by the body permitting flow of liquid in the bore onlyin the direction of said outlet; 7

a massive block of rigid material secured to said cylinder adjacent theend of the latter proximal said outlet there being a chamber in saidblock communicating with the outlet;

a pressure tank in communication with the chamber for receiving liquidtherefrom;

a check valve in the chamber for permitting flow of fluid therethroughonly in the direction from the outlet to the tank;

an eccentric operably coupled with said body for reciprocating thelatter, said eccentric having :a driving element and a driven element,the latter being rotatable on an axis relatively closely spaced to theaxis of rotation of the driving element for imparting short strokes tosaid body; and

prime mover means operably coupled with the eccentric for operating thelatter to drive the piston.

References Cited in the file of this patent UNITED STATES PATENTS833,457 Hammond Oct. 16, 1906 2,794,344 Boren June 4, 1957 2,915,986Sisson Dec. 8, 1959 3,006,282 Sisson Oct. 31, 1961 3,008,421 Bayer Nov.14, 1961 3,059,586 Brailsford Oct. 23, 1962 FOREIGN PATENTS 1,218,349France May 10, 1960

